/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2011. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
#ifndef __ERL_HASH_H__
#define __ERL_HASH_H__
#include "sys.h"
Eterm erts_hashmap_get(Eterm key, Eterm map);
/* erl_term.h stuff */
#define make_hashmap(x) make_boxed((Eterm*)(x))
#define make_hashmap_rel make_boxed_rel
#define is_hashmap(x) (is_boxed((x)) && is_hashmap_header(*boxed_val((x))))
#define is_hashmap_header(x) (((x) & (_TAG_HEADER_MASK)) == _TAG_HEADER_HASHMAP)
#define hashmap_val(x) _unchecked_boxed_val((x))
#define hashmap_val_rel(RTERM, BASE) hashmap_val(rterm2wterm(RTERM, BASE))
/* HASH */
#if defined(__GNUC__)
#define hashmap_bitcount(x) (Uint32) __builtin_popcount((unsigned int) (x))
#else
const Uint32 SK5 = 0x55555555, SK3 = 0x33333333;
const Uint32 SKF0 = 0xF0F0F0F, SKFF = 0xFF00FF;
/* CTPOP emulation */
Uint32 hashmap_bitcount(Uint32 map) {
map -= (( map >> 1 ) & SK5 );
map = ( map & SK3 ) + (( map >> 2 ) & SK3 );
map = ( map & SKF0 ) + (( map >> 4 ) & SKF0);
map += map >> 8;
return ( map + ( map >> 16)) & 0x3F;
}
#endif
/* hamt nodes v2.0
*
* node :: leaf | array | bitmap
* head
*/
/* the head-node is a bitmap or array with an untagged size
*/
typedef struct hashmap_head_s {
Eterm thing_word;
Uint size;
Eterm items[1];
} hashmap_head_t;
/* the bitmap-node
* typedef struct hashmap_bitmap_node_s {
* Eterm thing_word;
* Eterm items[1];
* } hashmap_bitmap_node_t;
*
* the array-node is a tuple
* typedef struct hashmap_bitmap_node_s {
* Eterm thing_word;
* Eterm items[1];
* } hashmap_bitmap_node_t;
*
* the leaf-node
* cons-cell
*/
/* thing_word tagscheme
* Need two bits for map subtags
*
* Original HEADER representation:
*
* aaaaaaaaaaaaaaaa aaaaaaaaaatttt00 arity:26, tag:4
*
* For maps we have:
*
* vvvvvvvvvvvvvvvv aaaaaaaamm111100 val:16, arity:8, mtype:2
*
* unsure about trailing zeros
*
* map-tag:
* 00 - flat map tag (non-hamt) -> val:16 = #items
* 01 - map-node bitmap tag -> val:16 = bitmap
* 10 - map-head (array-node) -> val:16 = 0xffff
* 11 - map-head (bitmap-node) -> val:16 = bitmap
*/
/* erl_map.h stuff */
#define MAP_HEADER_TAG_SZ (2)
#define MAP_HEADER_ARITY_SZ (8)
#define MAP_HEADER_VAL_SZ (16)
#define MAP_HEADER_TAG_FLAT (0x0)
#define MAP_HEADER_TAG_HAMT_NODE_BITMAP (0x1)
#define MAP_HEADER_TAG_HAMT_HEAD_ARRAY (0x2)
#define MAP_HEADER_TAG_HAMT_HEAD_BITMAP (0x3)
#define MAP_HEADER_TYPE(Hdr) (((Hdr) >> (_HEADER_ARITY_OFFS)) & (0x3))
#define MAP_HEADER_ARITY(Hdr) (((Hdr) >> (_HEADER_ARITY_OFFS + MAP_HEADER_TAG_SZ)) & (0xff))
#define MAP_HEADER_VAL(Hdr) (((Hdr) >> (_HEADER_ARITY_OFFS + MAP_HEADER_TAG_SZ + MAP_HEADER_ARITY_SZ)) & (0xffff))
#define is_hashmap_header_head(x) ((MAP_HEADER_TYPE(x) & (0x2)))
#define MAKE_MAP_HEADER(Type,Arity,Val) \
(_make_header(((((Uint16)(Val)) << MAP_HEADER_ARITY_SZ) | (Arity)) << MAP_HEADER_TAG_SZ | (Type) , _TAG_HEADER_HASHMAP))
#define MAP_HEADER_HAMT_HEAD_ARRAY \
MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_HEAD_ARRAY,0x1,0xffff)
#define MAP_HEADER_HAMT_HEAD_BITMAP(Bmp) \
MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_HEAD_BITMAP,0x1,Bmp)
#define MAP_HEADER_HAMT_NODE_BITMAP(Bmp) \
MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_NODE_BITMAP,0x0,Bmp)
#define HAMT_HEAD_EMPTY_SZ (2)
#define HAMT_NODE_ARRAY_SZ (17)
#define HAMT_HEAD_ARRAY_SZ (18)
#define HAMT_NODE_BITMAP_SZ(n) (1 + n)
#define HAMT_HEAD_BITMAP_SZ(n) (2 + n)
#define _HEADER_MAP_SUBTAG_MASK (0xfc) /* 2 bits maps tag + 4 bits subtag + 2 ignore bits */
/* SUBTAG_NODE_ARRAY is in fact a tuple with 16 elements */
#define HAMT_SUBTAG_NODE_ARRAY (((16 << _HEADER_ARITY_OFFS) | ARITYVAL_SUBTAG) & _HEADER_MAP_SUBTAG_MASK)
#define HAMT_SUBTAG_NODE_BITMAP ((MAP_HEADER_TAG_HAMT_NODE_BITMAP << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
#define HAMT_SUBTAG_HEAD_ARRAY ((MAP_HEADER_TAG_HAMT_HEAD_ARRAY << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
#define HAMT_SUBTAG_HEAD_BITMAP ((MAP_HEADER_TAG_HAMT_HEAD_BITMAP << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
#define hashmap_index(hash) (((Uint32)hash) & 0xf)
#endif
